Do expect T-Mobile users to be happy with the fact that a Wi-Fi calling indicator is set to debut. In the past, although T-Mobile users were able to make use of Wi-Fi calling, the presence of an indicator would mean one can be 100% sure that one is currently connected to the service itself – without any more question marks hanging in the air.
Other that that, there will also be the standard slew of bug fixes as well as general improvements, in addition to the ability to change Home Data to HomeKit in Settings > Privacy. One is also able to swipe open Spotlight faster than before, while the brightness controls have also been removed from the Wallpaper settings panel. Small touches such as a new sound right after a voice message is sent on Messages will also endear folks to iOS 8 even more, I believe. Expect the next update of iOS 8 beta for developers to arrive in the middle of this month (15th of August), while the rest of the world looks forward to an October roll out of the final version of iOS 8. Which would be just in time for the iPhone 6, aye?